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Consumption of sugar sweetened beverages (SSBs) in infants and young children are less explored in Asian populations. The Growing in Singapore Towards healthy Outcomes (GUSTO) cohort study examined associations between SSB intakes at ages 18 months and 5 years with adiposity measures at age 6 years. We studied Singaporean infants/children with SSB intake assessed by food frequency questionnaires (FFQ) at ages 18 months (n=555) and 5 years (n=767). The median (interquartile range) for SSB intakes is 28(5.5-98) ml at age 18 months and 111 (57-198) ml at age 5 years. Associations between SSB intakes (100 ml/day increments and tertile categories) and adiposity measures (BMI standard deviation scores (s.d. unit), sum of skinfolds (SSFs)) and overweight/obesity status were examined using multivariable linear and Poisson regression models, respectively. After adjusting for confounders and additionally for energy intake, SSB intakes at age 18 months were not significantly associated with later adiposity measures and overweight/obesity outcomes. In contrast, at age 5 years, SSB intakes when modelled as 100ml/day increments were associated with higher BMI by 0.09 (95% CI: 0.02, 0.16) s.d. unit, higher SSF thickness by 0.68 (0.06, 1.44) mm, and increased risk for overweight/obesity by 1.2 times (1.07, 1.23) at age 6 years. Trends were consistent with SSB intakes modelled as categorical tertiles. In summary, SSB intake in young childhood is associated with higher risks of adiposity and risk for overweight/obesity. Public health policies working to reduce SSB consumption need to focus on prevention programs targeted at young children.

Early life adversity (ELA) has been associated with inflammation and immunosenescence, as well as hyporeactivity of the HPA axis. Because the immune system and the HPA axis are tightly intertwined around the glucocorticoid receptor (GR), we examined peripheral GR functionality in the EpiPath cohort among participants who either had been exposed to ELA (separation from parents and/or institutionalization followed by adoption; n = 40) or had been reared by their biological parents (n = 72).

Expression of the strict GR target genes FKBP5 and GILZ as well as total and 1F and 1H GR transcripts were similar between groups. Furthermore, there were no differences in GR sensitivity, examined by the effects of dexamethasone on IL6 production in LPS-stimulated whole blood. Although we did not find differences in methylation at the GR 1F exon or promoter region, we identified a region of the GR 1H promoter (CpG 1-9) that showed lower methylation levels in ELA.

Our results suggest that peripheral GR signaling was unperturbed in our cohort and the observed immune phenotype does not appear to be secondary to an altered GR response to the perturbed HPA axis and glucocorticoid (GC) profile, although we are limited in our measures of GR activity and time points.

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Abstract

Complex oxides show a broad spectrum of intrinsic functionalities, such as ferroelectricity, magnetism, superconductivity or multiferroic behavior, which can be utilized and combined in electronic devices by the growth and design of heterostructures. Physical properties may arise in such multilayers that are not found in either of their constituents. A spectacular example for such a phenomenon, a conducting and highly mobile electron gas, is formed at the interface between the two insulating, dielectric perovskites LaAlO3 and SrTiO3 [1] which can be easily tuned by transverse electric fields [2]. In our contribution we will present recent studies of the microstructure of the multilayer and we will correlate them with the transport properties of the electron gas. [1] A. Ohtomo, H. Y. Hwang, Nature 427, 423-426 (2004). [2] S. Thiel, G. Hammerl, A. Schmehl, C. W. Schneider, J. Mannhart, Science 313, 1942-1945 (2006).

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Abstract

Description: Semiconductor physics contains a rich body of theory and working designs. However, their material properties seem to be reaching their limits. Perovskite oxides on the other hand have abundant physical properties, but are still under active investigation. The advent of RHEED-monitoring of pulsed laser deposition allows for the fabrication of structures with single unit cell (4 Å) thick layers. In this way we may be able to fabricate quantum well structures for both applications and fundamental investigations. Superlattices of the Mott insulator LaTiO3 (LTO) and the band gap insulator SrTiO3 (STO) form such a structure. The superlattices are metallic, both as-grown and post-annealed [1]. This has been attributed to the existence of metallic states at the interfaces between LTO and STO [2]. At these interfaces the electron density is found to extend about 10 Å into the STO. However, theoretically, the required length scale for quantum confinement is of the order of 4 Å. A possible way to increase this confinement is to use a buffer material with a larger band gap than that of LTO (similar to semiconductor band gap engineering) and/or with a lower dielectric constant [2]. LaAlO3 (LAO) is such a material (ΔELAO = 5.6 eV vs. ΔESTO = 3.2 eV, εLAO = 24 vs. εSTO = 300). Here we report on the growth of LTO/LAO superlattices on STO substrates. As-grown superlattices of LTO/LAO are metallic, while post-annealing turns them insulating. This may be explained from a disorder-order transition in a 2D Mott-Hubbard model [3]. XPS and EELS measurements of the titanium valence show interesting differences for LTO layers close to and far away from the sample surface. The former, for thin LAO capping layers, show the presence of Ti4+ while the latter only have Ti3+. Hard XPS of samples with varying capping layer thickness shows an exponential dependence of the Ti3+ contents on a length scale of about 5 unit cells. [1] A. Ohtomo et al., Nature 419, 378-380 (2002). [2] S. Okamoto & A.J. Millis, Phys. Rev. B 70, 075101 (2004). [3] D. Heidarian & N. Trivedi, Phys. Rev. Lett. 93, 126401 (2004).

We report on a new type of polymer electrolyte fuel cell based on a hydroxide ion conductive polymer combined with a non-noble chromium–nickel (Cr–Ni) catalyst for the oxygen reduction reaction (ORR). We study variable fractions of Cr in Ni by density functional theory simulating the thermodynamic potentials characterizing the ORR. We found increased ORR catalytic activity employing the rotating disk electrode technique. The polarization curve and power densities measured for the constructed fuel cell indicate considerable performance improvement with the Cr–Ni catalyst. Thus we expect that this kind of fuel cell may open up alternative routes in fuel cell research using non-noble catalysts.

Summary

Abstract

Important synergies and complementarities exist between trade liberalization initiatives and the application of measures to suppress anti-competitive practices or arrangements. Both anti-competitive practices of firms and state-orchestrated arrangements that restrict competition can undermine the gains from trade in myriad ways. Moreover, trade liberalization can be a powerful tool for addressing competition policy concerns. Whether there is a need to develop for more explicit linkages between national competition policies and the multilateral trading system remains an unresolved question in debates surrounding the future of the World Trade Organization (WTO). The role of competition policy is, however, increasingly being addressed by working parties during the accessions of new WTO members. This chapter finds that, in a vast majority of accessions, the acceding economy is requested to provide information on its domestic competition policy regime. In approximately 80 per cent of all accessions, the acceding parties have made notifications on aspects such as the objectives of the regime, its enforcement mechanisms by relevant agencies, as well as on work under way to put in place an effective competition regime where one is not already extant. This, in itself, shows a clear recognition and acceptance by WTO members of the importance of competition policy as a tool of economic integration. The complementarity between WTO law and competition policy, however, is broader than what is reflected in notifications and observations regarding competition legislation per se. Consequently, the analysis in this chapter also presents an in-depth study of the wider impact of competition in the WTO accession process, taking into account the information provided on aspects of the domestic regime dealing with state monopolies and the treatment of state-owned enterprises (SOEs).

Important synergies or complementarities exist between international trade liberalization and competition law and policy (Anderson and Müller, 2015). Competition policy aims at enhancing consumer welfare and economic growth by promoting competition and deterring practices that restrict it. The intended results are lower prices, enhanced product variety and quality, innovation, and sustainable growth and development. These goals are congruent and powerfully synergistic with those of the multilateral trading system.

Whether there is a need for more explicit linkages between national competition policies and the multilateral trading system – and, if so, what should be the content of related disciplines – currently is an unresolved question in debates surrounding the future of the WTO (Anderson and Müller, 2015).

Electron tomography has become a valuable and widely used tool for studying the three-dimensional nanostructure of materials and biological specimens. However, the incomplete tilt range provided by conventional sample holders limits the fidelity and quantitative interpretability of tomographic images by leaving a “missing wedge” of unknown information in Fourier space. Imaging over a complete range of angles eliminates missing wedge artifacts and dramatically improves tomogram quality. Full-range tomography is usually accomplished using needle-shaped samples milled from bulk material with focused ion beams, but versatile specimen preparation methods for nanoparticles and other fine powders are lacking. In this work, we present a new preparation technique in which powder specimens are supported on carbon nanofibers that extend beyond the end of a tungsten needle. Using this approach, we produced tomograms of platinum fuel cell catalysts and gold-decorated strontium titanate photocatalyst specimens. Without the missing wedge, these tomograms are free from elongation artifacts, supporting straightforward automatic segmentation and quantitative analysis of key materials properties such as void size and connectivity, and surface area and curvature. This approach may be generalized to other samples that can be dispersed in liquids, such as biological structures, creating new opportunities for high-quality electron tomography across disciplines.

Roundup is a glyphosate-based herbicide (GBH) widely used in agriculture and may cause toxic effects in non-target organisms. Model organisms, as zebrafish, and analysis of gene expression by reverse transcription-quantitative PCR (RT-qPCR) could be used to better understand the Roundup toxicity. A prerequisite for RT-qPCR is the availability of appropriate reference genes; however, they have not been described for Roundup-exposed fish. The aim of this study was to evaluate the expression stability of six reference genes (rpl8, β-act, gapdh, b2m, ef1α, hprt1) and one expressed repetitive element (hatn10) in organs of males (brain, gill, testis) and females (ovary) of zebrafish exposed to Roundup WG at three concentrations (0.065, 0.65 and 6.5 mg N-(phosphonomethyl) glycine/l) for 7 days. Genes were ranked by geNorm, NormFinder, BestKeeper, Delta Ct and RefFinder, and their best combinations were determined by geNorm and NormFinder programs. The two most stable ranked genes were specific to each organ: gill (β-act; rpl8); brain (rpl8; β-act); testis (ef1α; gapdh); and ovary (rpl8; hprt1). The cat transcript level was used to evaluate the effect of normalization with these reference genes. These are the first suitable reference genes described for the analysis of gene expression in organs of Roundup-exposed zebrafish, and will allow investigations of the molecular mechanisms of Roundup toxicity.

Recent evidence shows that the serotonin 2A receptor (5-hydroxytryptamine2A receptor, 5-HT2AR) is critically involved in the formation of visual hallucinations and cognitive impairments in lysergic acid diethylamide (LSD)-induced states and neuropsychiatric diseases. However, the interaction between 5-HT2AR activation, cognitive impairments and visual hallucinations is still poorly understood. This study explored the effect of 5-HT2AR activation on response inhibition neural networks in healthy subjects by using LSD and further tested whether brain activation during response inhibition under LSD exposure was related to LSD-induced visual hallucinations.

Methods

In a double-blind, randomized, placebo-controlled, cross-over study, LSD (100 µg) and placebo were administered to 18 healthy subjects. Response inhibition was assessed using a functional magnetic resonance imaging Go/No-Go task. LSD-induced visual hallucinations were measured using the 5 Dimensions of Altered States of Consciousness (5D-ASC) questionnaire.

Results

Relative to placebo, LSD administration impaired inhibitory performance and reduced brain activation in the right middle temporal gyrus, superior/middle/inferior frontal gyrus and anterior cingulate cortex and in the left superior frontal and postcentral gyrus and cerebellum. Parahippocampal activation during response inhibition was differently related to inhibitory performance after placebo and LSD administration. Finally, activation in the left superior frontal gyrus under LSD exposure was negatively related to LSD-induced cognitive impairments and visual imagery.

Conclusion

Our findings show that 5-HT2AR activation by LSD leads to a hippocampal–prefrontal cortex-mediated breakdown of inhibitory processing, which might subsequently promote the formation of LSD-induced visual imageries. These findings help to better understand the neuropsychopharmacological mechanisms of visual hallucinations in LSD-induced states and neuropsychiatric disorders.

A narrow bridge of floating ice that connected the Wilkins Ice Shelf, Antarctica, to two confining islands eventually collapsed in early April 2009. In the month preceding the collapse, we observed deformation of the ice bridge by means of satellite imagery and from an in situ GPS station. TerraSAR-X images (acquired in stripmap mode) were used to compile a time series. The ice bridge bent most strongly in its narrowest part (westerly), while the northern end (near Charcot Island) shifted in a northeasterly direction. In the south, the ice bridge experienced compressive strain parallel to its long axis. GPS position data were acquired a little south of the narrowest part of the ice bridge from 19 January 2009. Analysis of these data showed both cyclic and monotonic components of motion. Meteorological data and re-analysis of the output of weather-prediction models indicated that easterly winds were responsible for the cyclic motion component. In particular, wind stress on the rough ice melange that occupied the area to the east exerted significant pressure on the ice bridge. The collapse of the ice bridge began with crack formation in the southern section parallel to the long axis of the ice bridge and led to shattering of the southern part. Ultimately, the narrowest part, only 900 m wide, ruptured. The formation of many small icebergs released energy of >125 ×106 J.

On uncrevassed regions of polythermal glaciers, englacial conduits can form by incision of supraglacial stream channels followed by roof closure. The origin and evolution of examples in Longyearbreen, Svalbard, and Khumbu Glacier, Nepal, were determined by speleological survey. The development of perennial incised channels requires that incision is significantly faster than glacier surface ablation, and thus will be favoured by high meltwater discharges in combination with cool climatic conditions or thick debris cover. Incised canyons can become blocked by drifted winter snow, refrozen meltwater, ice rafting from non-local sources (allochthonous breccias) and roof collapses (autochthonous breccias). Conduit closure can also occur in response to ice creep, particularly at depth. Following isolation from the surface, englacial conduits continue to evolve by vadose incision down to local base level. In the case of Longyearbreen, incision allowed the channel to reach the glacier bed, but on Khumbu Glacier deep incision is prevented because an effectively impermeable terminal moraine provides a high base level for the glacier drainage system. During our period of observations, deeper parts of the Longyearbreen conduit became blocked by a combination of ice accumulation and creep, causing the stream course to be re-routed to higher levels. On that glacier, incision, blockage and upward re-routing are cyclic. We conclude that ‘cut and closure’ is the dominant mechanism of englacial conduit formation on uncrevassed regions of polythermal glaciers.

We present results from a multiwavelength study of the blazar PKS 1954–388 at radio, UV, X-ray, and gamma-ray energies. A RadioAstron observation at 1.66 GHz in June 2012 resulted in the detection of interferometric fringes on baselines of 6.2 Earth-diameters. This suggests a source frame brightness temperature of greater than 2 × 1012 K, well in excess of both equipartition and inverse Compton limits and implying the existence of Doppler boosting in the core. An 8.4-GHz TANAMI VLBI image, made less than a month after the RadioAstron observations, is consistent with a previously reported superluminal motion for a jet component. Flux density monitoring with the Australia Telescope Compact Array confirms previous evidence for long-term variability that increases with observing frequency. A search for more rapid variability revealed no evidence for significant day-scale flux density variation. The ATCA light-curve reveals a strong radio flare beginning in late 2013, which peaks higher, and earlier, at higher frequencies. Comparison with the Fermi gamma-ray light-curve indicates this followed ~ 9 months after the start of a prolonged gamma-ray high-state—a radio lag comparable to that seen in other blazars. The multiwavelength data are combined to derive a Spectral Energy Distribution, which is fitted by a one-zone synchrotron-self-Compton (SSC) model with the addition of external Compton (EC) emission.

Summary

On Perspectives. Mathematical logic arose from a concern with the nature and the limits of rational or mathematical thought, and from a desire to systematise the modes of its expression. The pioneering investigations were diverse and largely autonomous. As time passed, and more particularly in the last two decades, interconnections between different lines of research and links with other branches of mathematics proliferated. The subject is now both rich and varied. It is the aim of the series to provide, as it were, maps or guides to this complex terrain. We shall not aim at encyclopaedic coverage; nor do we wish to prescribe, like Euclid, a definitive version of the elements of the subject. We are not committed to any particular philosophical programme. Nevertheless we have tried by critical discussion to ensure that each book represents a coherent line of thought; and that, by developing certain themes, it will be of greater interest than a mere assemblage of results and techniques.

The books in the series differ in level: some are introductory some highly specialised. They also differ in scope: some offer a wide view of an area, others present a single line of thought. Each book is, at its own level, reasonably self contained. Although no book depends on another as prerequisite, we have encouraged authors to fit their book in with other planned volumes, sometimes deliberately seeking coverage of the same material from different points of view. We have tried to attain a reasonable degree of uniformity of notation and arrangement. However, the books in the series are written by individual authors, not by the group. Plans for books are discussed and argued about at length. Later, encouragement is given and revisions suggested. But it is the authors who do the work; if as we hope, the series proves of value, the credit will be theirs.

History of the Ω-Group. During 1968 the idea of an integrated series of monographs on mathematical logic was first mooted. Various discussions led to a meeting at Oberwolfach in the spring of 1969. Here the founding members of the group (R. O. Gandy, A. Levy, G. H. Muller, G. E. Sacks, D. S. Scott) discussed the project in earnest and decided to go ahead with it. Professor F. K. Schmidt and Professor Hans Hermes gave us encouragement and support.